Nanoparticle-Decorated Surfaces for the Study of Cell-Protein-Substrate Interactions

2004 ◽  
Vol 845 ◽  
Author(s):  
Jake D. Ballard ◽  
Ludovico M. Dell'Acqua-Bellavitis ◽  
Rena Bizios ◽  
Richard W. Siegel
Keyword(s):  
Silica Nanoparticles ◽  
Surface Coverage ◽  
Silicon Oxide ◽  
Substrate Surface ◽  
Silicon Surfaces ◽  
Native Oxide ◽  
Cell Protein ◽  
Fabrication And Characterization ◽  
Nanoscale Features

ABSTRACTThe present study was motivated by the need for accurately-controlled and well-characterized novel biomaterial formulations for the study of cell-protein-material interactions. For this purpose, the current research has focused on the design, fabrication and characterization of model native oxide-coated silicon surfaces decorated with silica nanoparticles of select sizes, and has examined the adhesion of osteoblasts and fibroblasts on these nanoparticle-decorated surfaces. The results demonstrate the capability to deposit nanoparticles of select diameters and substrate surface coverage onto native silicon oxide-coated silicon, the firm attachment of these nanoparticles to the underlying native silicon oxide, and that nanoparticle size and coverage modulate adhesion of osteoblasts and fibroblasts to these substrates. The material formulations tested provide a well-controlled and well-characterized set of model substrates needed to study the effects of nanoscale features on the functions of cells that are critical to the clinical fate of implantable biomaterials.

TEM characterization of silicon epitaxial layer grown on Si-TaS2, eutectic composites

1991 ◽  
Vol 49 ◽  
pp. 802-803
Author(s):  
C.M. Sung ◽  
M. Levinson ◽  
M. Tabasky ◽  
K. Ostreicher ◽  
B.M. Ditchek
Keyword(s):  
Substrate Surface ◽  
Bulk Sample ◽  
Surface Cleaning ◽  
Native Oxide ◽  
Czochralski Growth ◽  
Ion Milling ◽  
Cross Sectional ◽  
Cleaning Methods ◽  
Field Emission Cathodes

Directionally solidified Si/TaSi2 eutectic composites for the development of electronic devices (e.g. photodiodes and field-emission cathodes) were made using a Czochralski growth technique. High quality epitaxial growth of silicon on the eutectic composite substrates requires a clean silicon substrate surface prior to the growth process. Hence a preepitaxial surface cleaning step is highly desirable. The purpose of this paper is to investigate the effect of surface cleaning methods on the epilayer/substrate interface and the characterization of silicon epilayers grown on Si/TaSi2 substrates by TEM.Wafers were cut normal to the <111> growth axis of the silicon matrix from an approximately 1 cm diameter Si/TaSi2 composite boule. Four pre-treatments were employed to remove native oxide and other contaminants: 1) No treatment, 2) HF only; 3) HC1 only; and 4) both HF and HCl. The cross-sectional specimens for TEM study were prepared by cutting the bulk sample into sheets perpendicular to the TaSi2 fiber axes. The material was then prepared in the usual manner to produce samples having a thickness of 10μm. The final step was ion milling in Ar+ until breakthrough occurred. The TEM samples were then analyzed at 120 keV using the Philips EM400T.

Nanowire Arrays for Thermoelectric Devices

2003 ◽  
Author(s):  
Woo C. Kim ◽  
Alexis R. Abramson ◽  
Scott T. Huxtable ◽  
Arun Majumdar ◽  
Yiying Wu ◽  
...  
Keyword(s):  
Ohmic Contacts ◽  
Nanowire Arrays ◽  
Native Oxide ◽  
Thermoelectric Device ◽  
Growth Mechanisms ◽  
Thermoelectric Devices ◽  
Current Voltage ◽  
Semiconductor Junction ◽  
Fabrication And Characterization

This study reports on the fabrication and characterization of two prototype thermoelectric devices constructed of either silicon (Si) or bismuth telluride (Bi2Te3) nanowire arrays. The growth mechanisms and fabrication procedures of the Si and Bi2Te3 devices are different as described in this paper. To characterize the thermoelectric device components, current-voltage (I-V) characteristics were first used to estimate their performance. For the Si device, the I-V characteristics suggest ohmic contacts at the metal-semiconductor junction. For the Bi2Te3 device, the I-V characteristics curve showed a rectifying contact. Either low doping of the Bi2Te3 or surface contamination, i.e. native oxide, may cause the rectifying contact. The reversible Peltier effects occurring within the Si device were analyzed using a micro-thermocouple. Results indicated possible limitations of using Si nanowire arrays for the thermoelectric device.

Characterization of HF Treated (100) Si Surfaces by Surface Charge Analysis (SCA)

1992 ◽  
Vol 259 ◽  
Author(s):  
Jon T. Fitch
Keyword(s):  
Electrical Properties ◽  
Surface Charge ◽  
Chemical Bonding ◽  
Oxide Thickness ◽  
Silicon Surfaces ◽  
Native Oxide ◽  
Charge Analysis ◽  
The Stability ◽  
Over Time

ABSTRACTSurface Charge Analysis (SCA), and ellipsometry have been used to study the stability over time of HF treated (100) silicon surfaces as a function of the post-HF rinse time. Using SCA, the electrical properties of the chemical terminating layer of these silicon surfaces were measured. The surfaces which remained native oxide free the longest (−10 hours) had very low Qox and Dit values on the order of 1.0 × 1011/cm2 and 5.0 × 1010 eV−lcm−2, respectively. A good correlation was found between Dit and the native oxide thickness measured by ellipsometry. This and other results are discussed in terms of the chemical bonding on the silicon surfaces.

Fabrication and characterization of aluminum nitride pedestal-type optical waveguide

2014 ◽  
Vol 92 (7/8) ◽  
pp. 951-954 ◽  
Author(s):  
M.A. Alvarado ◽  
M.V. Pelegrini ◽  
I. Pereyra ◽  
T.A.A. de Assumpção ◽  
L.R.P. Kassab ◽  
...  
Keyword(s):  
Thin Films ◽  
Aluminum Nitride ◽  
Optical Waveguides ◽  
Silicon Oxide ◽  
Crystalline Silicon ◽  
Pure Aluminum ◽  
Core Layer ◽  
Cladding Layer ◽  
Fabrication And Characterization

In this paper we present the fabrication and characterization of pedestal-type optical waveguides using aluminum nitride (AlN) as core layer. To the best knowledge of the authors, the utilization of AlN as core layer in pedestal-type waveguides has not been studied. The AlN thin films were obtained by radio frequency reactive magnetron sputtering from a pure aluminum target. The AlN refractive index was determined by ellipsometry. The optical waveguides were fabricated by the pedestal technique, which consists in etching the silicon oxide lower cladding layer before depositing the core layer. Thus, the waveguide geometrical definition is simplified because etching the AlN core is not necessary. AlN thin films of 0.6, 1, and 1.2 μm thick were deposited on thermally grown silicon dioxide using crystalline silicon (100) as substrate. The pedestal profile was defined using conventional photolithography, followed by plasma etching of the cladding layer. Optical propagation losses were measured for pedestal heights of 1 μm and widths from 1 to 100 μm.

Fabrication and Characterization of RF Magnetron Sputtered Silicon Oxide Films

2014 ◽  
Vol 970 ◽  
pp. 102-105
Author(s):  
Jian Wei Hoon ◽  
Kah Yoong Chan ◽  
Cheng Yang Low
Keyword(s):  
Indium Tin Oxide ◽  
Silicon Oxide ◽  
Rf Magnetron Sputtering ◽  
Surface Topology ◽  
Sputtering Deposition ◽  
Force Microscopy ◽  
Glass Substrates ◽  
Atomic Force ◽  
Fabrication And Characterization

In this work, silicon dioxide (SiO2) films were fabricated on indium tin oxide (ITO) coated glass substrates by radio frequency (RF) magnetron sputtering deposition technique. The deposition rate of the magnetron sputtered SiO2 films was investigated. The SiO2 films were characterized with the atomic force microscopy (AFM) for their surface topology. In addition, the electrical insulating strength of the magnetron sputtered SiO2 was examined.

Chemical Control of Surfaces: From Fundamental Understanding to Practical Application

2012 ◽  
Vol 195 ◽  
pp. 65-70
Author(s):  
Melissa A. Hines
Keyword(s):  
Atomic Scale ◽  
Silicon Surfaces ◽  
Native Oxide ◽  
Native Oxide Layer ◽  
Microelectronics Industry ◽  
Industrial Adoption ◽  
Detrimental Impact ◽  
Metallic Impurities ◽  
Acidic Hydrogen

In the early days of the microelectronics industry, it became clear that even trace contaminants could have detrimental impact on the electronic properties of fabricated devices. This realization led to the development of the so-called RCA clean for silicon surfaces [], which uses sequential baths in basic and acidic hydrogen peroxide solutions, now known as SCA-1 and SCA-2, to oxidize organic materials, remove particulates, and bind metallic impurities. The detailed characterization of this process as well as its simplicity and economic viability soon led to its widespread industrial adoption. Although the RCA clean includes an optional etch in dilute HF between the two cleaning solutions to remove the native oxide layer, the overall process results in an extremely clean but electronically defectiveoxide-terminatedand thus extremely hydrophilic silicon surface, which we now know is quite rough on an atomic scale [].

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